Conventional salt water boat lift mechanisms typically employ one or more winch driven cables to raise and lower a boat-supporting platform. In a single or three-stage lift, the distal or terminal end of each cable is normally fastened to one of the cradle beams of the platform. Two-stage boat lifts connect the cables to the platform by pulleys which are themselves mounted to the cradle beams. Each cable in the two stage lift is fastened at its terminal end to a cable beam, which accommodates a winch or winder. In either case, the cable is fastened to a respective beam at essentially a single point of attachment.
Currently, when a boat lift is constructed, the terminal end of each cable must be attached at the factory. This operation is required to ensure that the terminal connection is absolutely secure. On site attachment by often unsophisticated or poorly trained installers is simply too unreliable. Therefore, the lift manufacturer itself secures the terminal end of each cable to its desired attachment point, typically by means of a connecting loop, which is formed at the terminal end of the cable.
It is very difficult, if not impossible, to string the above described cable loop through the pulleys of a multiple stage boat lift. Accordingly, most boat lift cables are strung and installed in a rearward direction. After being fastened at its terminal point, the cable is strung through the various pulleys. Finally, the proximal end of the cable is attached to the cable winder. This operation is normally performed on site. Fastening security is less critical at the proximal end of the cable. As the winder is operated and the cable is wrapped thereon, the winder circumferentially absorbs and distributes the lifting load. Little or no load is experienced at the proximal end of the cable.
Stringing the cable rearwardly from the terminal point of attachment to the winder presents several problems for the boat lift installer. This technique forces the installer to "field wind" the cables onto the winder during the installation process. Engaging the cable with the winder on site or in the field is awkward, as the installer must typically work over water at inconvenient heights. It would be far preferable to prewind the cables onto the winder at the factory, where this procedure could be performed faster, more conveniently and at far less expense. However, to date, this operation has not been widely used because of the reluctance to secure the terminal end of the cable in the field.
Securing the terminal end of the cable to its respective point of attachment and stringing the cable rearwardly to the winder also complicates cable adjustment. Following installation, it is often necessary to adjust the cable lengths to compensate for settling of the cable beam support pilings. Such settling normally occurs when a boat is first elevated by the lift. When the terminal end of the cable is permanently fixed at the factory, it is extremely difficult to make the necessary length adjustments. The cable must be detached from the winder and totally restrung. This is an extremely time consuming, awkward and inconvenient procedure.
Replacement of worn cables is another commonplace problem. Once again, the new cable must first be attached at its proximal end and then strung in a rearward direction to the winder. When a new cable is installed, its length almost always requires adjustment due to previous settling of the support pilings. The new cable must be detached and restrung to adjust that length.
Accordingly, the currently accepted practice of permanently attaching the terminal end of the boat lift cable to its respective point of attachment and stringing the cable rearwardly toward the winder complicates boat lift installation considerably and adds to the difficulty, time and expense of such installation. The need exists for a means of boat lift cable attachment, which enables the proximal end of the boat lift cable to be factory wound, the terminal end of the cable to be attached in the field, and the length of the cable to be adjusted quickly and conveniently, without having to totally restring the cable.